<?php

declare(strict_types=1);

class Int_VGT extends IPSModule
{
    public function Create()
    {
        parent::Create();

        $this->RegisterPropertyString("DeviceID", "");

        // Create handler script
        if (!@$this->GetIDForIdent("ReceiveScript")) {
            $id = IPS_CreateScript(0);
            IPS_SetName($id, "INTVGT_ReceiveHandler");
            IPS_SetIdent($id, "ReceiveScript");
            IPS_SetParent($id, $this->InstanceID);
            IPS_SetScriptContent($id, $this->GenerateReceiveScript());
        }
    }

    public function ApplyChanges()
    {
        parent::ApplyChanges();

        $gatewayID = $this->GetGatewayID();
        $deviceID = $this->ReadPropertyString("DeviceID");

        if ($gatewayID == 0 || $deviceID == "") {
            $this->SetStatus(104);
            return;
        }

        // Create MQTT devices
        $this->RegisterMQTTDevice("FeedbackRequest",
            "feedback-request/" . $deviceID);

        $this->RegisterMQTTDevice("RemoteControlResponse",
            "remote-control-response/" . $deviceID);

        $this->SetStatus(102);
    }

    private function RegisterMQTTDevice(string $ident, string $topic)
    {
        $guidMQTTDevice = "{043EA491-84DA-4DFD-B9D4-44B4E63F23D1}";

        $id = @$this->GetIDForIdent($ident);
        if ($id === false) {
            $id = IPS_CreateInstance($guidMQTTDevice);
            IPS_SetParent($id, $this->InstanceID);
            IPS_SetIdent($id, $ident);
            IPS_SetName($id, "MQTT Device: " . $ident);
        }

        IPS_SetProperty($id, "Active", true);
        IPS_SetProperty($id, "Topic", $topic);
        IPS_SetProperty($id, "Script", $this->GetIDForIdent("ReceiveScript"));
        IPS_ApplyChanges($id);

        return $id;
    }

    private function GetGatewayID(): int
    {
        $instance = IPS_GetInstance($this->InstanceID);
        return $instance['ConnectionID'];
    }

    private function GenerateReceiveScript(): string
    {
        return <<<PHP
<?php

\$parent = IPS_GetParent(\$_IPS['SELF']);

IPS_RequestAction(\$parent, "OnReceive", json_encode([
    "Topic" => \$_IPS['Topic'],
    "Value" => \$_IPS['VALUE']
]));

PHP;
    }

    public function RequestAction($ident, $value)
    {
        if ($ident === "OnReceive") {
            $data = json_decode($value, true);
            $this->OnReceiveMQTT($data["Topic"], $data["Value"]);
        }
    }

    private function OnReceiveMQTT(string $topic, string $value)
    {
        IPS_LogMessage("Int_VGT", "Received: $topic -> $value");

        $gatewayID = $this->GetGatewayID();

        // Auto responses (you can modify later)
        if (str_contains($topic, "feedback-request")) {
            MQTT_Publish($gatewayID,
                str_replace("request", "response", $topic),
                json_encode(["status" => "ok"])
            );
        }

        if (str_contains($topic, "remote-control-response")) {
            MQTT_Publish($gatewayID,
                str_replace("response", "feedback", $topic),
                $value
            );
        }
    }
}

?>